BioMedical Admissions Test (BMAT) Practice Test 2025 - Free BMAT Practice Questions and Study Guide

Huntington's Disease is classified as a dominant genetic disease because it is caused by a mutation in a single gene, specifically the HTT gene located on chromosome 4. In dominant disorders, only one copy of the mutated gene is necessary for a person to be affected by the disease. This means that individuals with just one copy of the mutated gene will exhibit symptoms of Huntington's Disease, regardless of the other allele they possess. As a result, this condition can be passed on from an affected parent to their offspring with a 50% chance of inheritance.

In contrast, recessive diseases require two copies of the mutated gene for the individual to express the disease. X-linked diseases are linked to genes on the X chromosome and typically affect males more than females due to the presence of only one X chromosome in males. Polygenic diseases result from the interaction of multiple genes and often present as complex traits rather than Mendelian disorders like Huntington's Disease.